Project Location
Seattle, WA

Community Roots Housing


Mass Timber Supplier/Fabricator

DCI Engineers

Affordable Housing, Mass Timber

General Contracting, Mass Timber Supply & Install, Preconstruction, Self-Perform

Pacific Northwest

Swinerton Office Location
Seattle, Washington

First Type IV-C Tall Mass Timber in Seattle, Design Assist, Workforce Housing, Wood Innovation Grant Recipient

The Heartwood project will bring workforce housing to central Seattle, filling a critical need for middle-income housing in the city. The project will make use of an innovative, eco-friendly building material: cross-laminated timber (CLT), which lowers the overall carbon footprint of the structure. When completed, Heartwood is anticipated to be one of Washington’s tallest CLT buildings.

This project received a $250,000 Wood Innovation Grant from the U.S. Forest Service to validate the feasibility of Type IV-C multifamily housing. Swinerton supported the U.S. Forest Service grant application and joined the project team in a design-build capacity for the overall construction including the mass timber structure.

Through the design phase, Swinerton worked with the architect and structural engineer to determine the optimal unit layout and structural grid to meet the programmatic and budget needs of the project. Swinerton has also led meetings with the Seattle Department of Construction & Inspections to highlight grey areas of the code for this new construction typology and to propose solutions that address fire and life safety during both construction and occupancy.

The building will house 126 studio and 1-bedroom apartments ranging from 324-488-square-feet. Swinerton is completing this design-build with atelierjones. The apartments will also feature a lobby, retail space, shared courtyard, fire pit, BBQ area, and multiple bike storage rooms. We performed extensive clash detection during preconstructuion to ensure the client received the look and usability they were wanting from the space. The design of the building features exposed glulam beams. The project will also be 4-star Built Green Certified.